Add HOW to buy guide for each known exchange

Signin gup to a new exchange can be daunting, and you don't know what documents you will need to KYC, how long it will take, limits, supported ramps, supported countries, new buying experiences and UI/UX etc. We can make life easier for people by making a guide for each venue where JOY can be traded, similar to this: https://xcadnetwork.com/buy-xcad

We can add it to the token page for example, adn then add a section on the landing page which funnels people there.